1. Field of the Invention
This invention relates to methods and devices for treating infarcted heart tissue using a percutaneously delivered deflection catheter.
2. Description of the State of the Art
Congestive heart failure is a major disease with a high mortality rate. The disease progresses cyclically, the cause being overcompensation of the heart muscle to make up for the loss of function from infarcted myocardium. As the heart continues to overcompensate, more tissue becomes infarcted, and the heart grows in size until the anatomical valve structures can no longer operate as intended. The resulting complications become extremely serious. Existing methods for treating congestive heart failure include the removal of infarct tissue and the constraint of the heart muscle.
Another approach for treating infarct myocardial tissue is the implantation of cells, such as mesenchymal stem cells, skeletal myoblasts, bone marrow mononuclear cells, etc., which will facilitate the revitalization of the infracted heart tissue. Hereafter, these types of materials, as well as solutions containing them, will be referred to as therapeutic agents. Delivery of therapeutic agents into the infarct tissue in a minimally-invasive way generally requires that a catheter access the Internal heart chamber wall in which the infarcted area exists. This access is achieved by tracking a catheter over a guidewire that has been placed through either the vena cava or aorta, and then through the appropriate heart valve(s), to the site of the infarct. It will be appreciated, that such a beating-heart, percutaneous approach must be made while the heart muscle pulses through systole and diastole, and therefore the target site is constantly moving locations. Given that there is often a need for multiple injections using these technologies, it can be extremely difficult to place the multiple injection sites in a controlled pattern within the dynamic environment. Repositioning the device can easily result in a non-uniform, inaccurate delivery of cell boluses into the target site. There is a need to overcome the difficulty and randomness of delivery that is associated with current cell therapy devices.